Refrigerator



Reiued Aug. 25, 1931 UNITED STATE-.s

PATENT OFFICE' HERBERT T. HERB, F PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION 0F PENNSYLVANIA BEFRIGERATOB.

Original No. 1,697,185, dated January 1, 1929, Serial No. 643,403, led J'une 4, 1928. Application for reissue led ctober 20, 1930. Serial No. -490,038.

My invention relates to refrigerating ma- I chines, particularly to small capacity machines of the 'compression type which are suitable for household use, and it has for an object to provide apparatus of the character designated which shall include evaporators having a high capacity and efficiency for absorbing heat.

It has for a further object to reduce the overall size of refrigerators of respective capacities by providing an evaporator of such shape and proportion as Will closely conform to the interior of `the refrigerator box and therefore occupy a minimum amount of space within the food storage chamber.

It has for a still further object to associate with the-evaporator adequate facilities for the manufacture of a substantial quantity of ice for table or similar use.

These and other objects, which will be made apparent throughout the further deseri )tion'of the invention, may be attained by t ie employment of the apparatus hereinafter described and illustrated in the accompanying drawings, in which:

Figure 1 is a view in longitudinal section of an evaporator installed in the cold-storage box of a compression refrigerator;

Fig; 2 is ai transverse sectional elevation taken on the line II-II of Fig. 1;

Fig. 3 is a longitudinal section taken on the line Ill-Ill of Fig. 2;

Fig. 4 is a transverse sectional elevation of the refrigerator box showing the circulation of air therein; i

Fig. 5 is a detail view of a combined spacer and stifiener employed in the construction of my evaporator;

Figs. 6 and 7 are partial views in section of two modified forms of construction 'l' or the circulating con'lpartmcnt of the evaporator;

Fig. Sis a View similar to Fig. 1, but showing the complete evaporator with the wall structure shown-in Fig. 7

Fig. 9 is a sectional view taken on the line IX-IX in Fig. 8, and

Fig. 10 is a sideview of shown in Fig. 8.

Compression refrigerators nominally comprise a chamber in which a Working iuid is evaporated at a relatively 10W temperature and pressure, a chamber in Which the vapors are condensed at a higher temperature and pressure, a compression mecha nism for transmitting the vapors from the evaporation chamber to the condensing chamber, and a valved conduit for returning the condensed fluid at a reduced pressure to the evapora 'on chamber. The cycle is continuous duri g any period of operation, heat heilig absorbed from' the medium surrounding 'the evaporation chamber to secure the desired refrigerating effect, which heat is removed from the the cooling unit -apparatus by bringing an outside medium into heat-exchanging relation tothe contents of the condensing chamber. Apparatus of this character generally operates intermittently, for example, a period of operation of from one to one and one-quarter hours being followed by a period of inactivity of from one and one-half to two hours, the length of the periods depending upon the duty imposed upon the refrigerator and upon the setting of the automatic devices for controlling the starting and stopping of the compression mechanism.

In the various types of compression refrigerators heretofore proposed, it has generally been the practice to provide evaporators of some suitable shape or proportions, having little regard for the inner contour of the refrigerator box. The arrangement of these evaporators within the box usually results in a considerable amount of unusable space being present in the upper portion thereof, as Well as presenting a path of considerable resistance and a non-uniform area of How for the circulation of air around the evaporators.

In my apparatus, I )rovide an evaporator of high etliciency whic is so designed, with respect to the inner contour of the refrigerator box, as to completely utilize the upper rtion thereof, leavin only sufficient space tween itscooling surfaces and the box as is rquireckfor sufficient air circulation. Furthermore, this air -space is of uniform How area throughout, thereby inducing a steady, uniform siphonic circulation of air within the' refrigerator box at all times. Because of the utilization of all available space in my apparatusz the size of the refrigerator box may materially lessened for respective capacities, resulting i n a decrease in radiating surface and a corresponding increase in eiliciency of the refrigerating machine.

It is customary in machines of this type, .to associate with the evaporation chamber or evaporator facilities for the manufacture of ice. In the various types of evaporators heretofore proposed, the ice manufacturing capacity has been very meagre and generally has not been suflicient to meet the requirements of the average household. In the eva rator of the present invention, ample facilities for the .production of relatively 'iarge quantities of ice are provided in the large interior chamber of the evaporator.

Referring to the drawings for a more. detaileddi'cription of my invention, I show in n refrigerator box having disv vtherein an evaporator 11 and superimposed-.L Qrpon the evaporator 11 is a surge ftank or header 12. The evaporator 11 is comdpf an inner heat conducting casing or shellV 13- and an outer heat conducting casingor shell 14, forming an ice making compartmentland a working fluid circu- 13 andthe outer casing 14 are maintained in spaced relation by a plurality of stiffeners 17. The sti'ener 17. as shown in Fig. 5, is provided with a bodvportion 18 having a length equal to the distance between the inner and outer casing. and'end portions 19 of relativelv smaller diameter. .a partof each end portion being riveted over upon the outside of the casings vand soldered thereto to Ainsure gas tightness. The working fiuid is confined within the circulating compartment 16 bv Hanging over the front' and rear end vportions 2 1 of 'the outer casing 14 andv welding or soldering the ends thereof to the inner casing 13.` It will be noted that the front Vand rear end portions 21 are connected to the inner casing 13 along a line short of the edges thereof. I have found from the actual manu factureof my apparatus. that such construcs tion greatly facilitates the making of a gas tight joint between lthe inner and outer cas- A relatively thin plate 23 extends across the 'realjof the ice' making compartment 15 and is secured at the edges thereof tothe latingcompartment 16. The inner casing inner casinfr 13. A similar plate 24 extends across the fzront of the ice maklng compartment and has provided therein suitable access A plurality of ice drawers or molds 29 ofany well-known construction may be placed upon the shelf 27 and upon the lower portion o the casing 13.

lVorking Huid is conveyed to the circulating compartment 16 of the evaporator by a conduit 31 which extends downwardly through the. surge tank 12 'and evaporator 1l and terminates near the bottom thereof. In order to facilitate assembly a i disassembly of in a Uaratus I ari-ance he lower or that port-ion of the conduit31 which is confined wi hin the ice making.compartment 15,' concentrically within a central supporting member 32, the outer'surface of the conduit being in Vbearing engagement therewith. A slight leakage of Working fluid upwardly between the conduit and the central supporting member is insufficient to materially affect the performance of the apparatus. The central supporting member 32 is provided with end portions 33 of smaller diameter whichi'extend beyond the inner casing. The central supporting member is welded or soldered to the upper and lower portions of the inner casing 13 and helps maintain them in spacedrelation.

Refrigerant vapors are discharged from the circulating compartment 16 by means of `a ,conduit 34 which communicates with the lower portion ofthe s urge tank 12. Disposed within the surge tank is an upwardly-extend# ingr sleeve member 35,`cl0sed at the lower end and supported upon the inlet conduit 31. The circular openlng between the upper end of the sleeve member35 and the surge tank 12 is for the assage of refrigerant vapor, while the liquld working Huid is conveyed through av small hole or restricted opening 36 provided in the sleeve member 35 below the working level of the liquid in the outer compartment of the surge tank. An outlet conduit 37 is arranged concentrically without the conduit 31 and, as shown, extends downwardly into the tank, making a tight joint therewith where it passesthrough the-upper portion. As shown in Fig. 4, a baille 38 is disposed beneath the evaporator and extends the longitudinal length of the refrigerator box. 4

Figs. 6 to 10 show modified forms of construction forthe evaporator which eliminate the use of the lstifl'eners 17. As shown in Fig. 6, the outer casing 14 is provided with a plurality of circular indentations 40 which register with similar indentations in the inner casing 13, the two casings being spot welded together where the respective indentations make contact as at 41. In Figs. 7 to 10, only the outer casing is indented, the indentations 42 being of sufficient depth to make contact with the fiat inner casing to which they are spot welded as at 43. By the use of either of thesetwo forms of cons ruction, a strong and substantially built evaporator may be produced at a low cost of manufacture.

The operation of the apparatus thus described is as follows: The circulating compartment 16 of the evaporator is completely filled and the surge tank is filled to a level, such as indicated on the drawings, with a suitable working fluid. This working fluid may consist of a combined refrigerant and lubricant which readily mix one with the other. Upon starting Athe compression mechanism (not shown) of the refrigerator, liquid working fluid is supplied through the inlet conduit 31 to the lower portion of the circulating compartment 16 of the evapo' rator. Cooling effectis then produced in normal manner by the vaporization of the cooling agent caused by the low vacuum pressure maintained in the evaporator by the compressor (not shown). Heat is absorbed from the refrigerator box, or, air surrounding the outer surfaces of the evaporator, as well as from the inner or ice making compartment.

In the use of a considerable number of suitable working fluids for refrigerators of this type, and especially where a mixed lubricant and refrigerant comprise the working fluid, evaporation produces a violent ehullition or foaming. By providing a surge tank 12 and locating it with respect to the evaporator as illustrated, this foam is carried over into the surge tank, insuring a body of liquid working fluid being present in the entire circulating compartment of the evaporator at all times. Because of the relatively high specific heat of the liquid` a maximum of cold storage or heat absorption consistent with the size of the evaporator is obtained.

Refrigerant vapor passes ont of the evaporatorby means of the conduit 34 and rises upwardly through the liquid working tinid to the Aupper portion of the surge tank. It then passes over the upper end of the sleeve. 35 and thence downwardly to the entrant portion of the outlet conduit 37 wherein it is once more conveyed to the suction of the compressor (not shown). The restricted opening 36, heilig located below the level of f the liquid working fluid within thc outer portion of the surge tank, a small amount of this lnid flows continuously to the outlet.

conduit 37, into the suction of the compressor andserves to lubricate the working parts thereof.

Refrigerators of this type are usually rovided with automatic control means wiich stop the operation of the compression mechlcompartment is independent of the tempera-- turev of the refrigerator box. Should ice not be fully formed during one operation of the machine, the temperature prevailing within the ice making compartment will remain substantially constant during the inactive period of the machine, and the manufacture of the ice will be resumed upon a restarting of the device.

A thermo-siphonic circulation of air within the refrigerator box is, as indicated by the arrows in Fig. 4, induced by the heat absorption of thel evaporator. The baille 38 is disposed at such angle as will tend to direct the warm air upwardly, toward the front of the box. It then passes over the top'and down past the sides and rear of the relatively cold evaporator to the food storage portion of the box. It will be noted that the air passages between the evaporator and the box'are of constant flow area throughout,A thereby minimizing resistance to flow and inducing a constant and efficient passage of air about the evaporator.

While I have shown my invention in but three forms, it will be obvious to those skilled in the art, that it is not so limited, but is susceptible of various other changes and modilications, withoutdeparting frolnthe spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are imposed by the prior art or.- asV are specifically set forth in the appended box, of a cooling element arranged within the refrigerator box and comprising a plurality, of compartments joined in stepped relation,

the joint connecting the compartments being exposed to the interior of the refrigerator box, one of said compartments forming an ice-making chamber and the other of said compartments forming a refrigerant expansion chamber.

3. The combination with a refrigerator box, of a cooling element disposed within the refrigerator box comprising an inner compartment forming an ice-making chamber andan outer compa rtmelit disposed about the inner 'compartment and forming a refrigerant expansion chamber, said ice-making chamber and said refrigerant expansion chamber being joined in stepped relation and so arranged that the joint is exposed to the interioof the refrigerator boit.I

4.Rcfrigerant liquid storage and evaporating means for a refrigerating apparatus comprising, in combination, a fabricated unitary structurecomprising a surge tank or Aheader providing a chamber for liquid and gaseous refrigerant, and a liquid-evaporating chamber positioned below the header andcomprising a pair of metallic casings spaced apart to forni a passage forliquid refrigerant, a cooling cliauiber within the caslngs,

` one of said casings being welded at its periphery to the other of said casuigs to provide a closed container for liquid refrigerant, said passage being in open conununication with the liquid in the header, the walls of said cooling chamber being submerged in liquid refrigerant and substantially uniformly exlposed to the liquid temperature, and means or maintaining said casings substantially rigid and in spaced relationship, said means comprising a plurality of welded portions uniting the casings intermediate their pe- I ri pheries.

,Y 5. 'In an evaporating unita header com` y' pri'sing a casing forming the sides and top of a' liquid and gas chamber, and a liqnid-dis tributing and spreading' chamber for heatexchange pui-poses, comprising a pair of spaced and nested casings directly connected to said first named casing and having the space between the casings closed at the ends and in communication with the Huid in the firsf-nicnt-ioned casing, said nested casings being in physical contact at spaced intervals intermediate vtheir peripheries, and means comprising welded portions for niaintainingthe second-named casings rigid and in spaced relation at the contacting intervals.

6. Refrigerant liquid storage and evapor'ating means for refri erating apparatus comprising a fabricate unitary structure Vformed of a pair of nested sheet-metal casi ngs spacedf apart but having one of said casings joined 'fat its periphery to the other of said casingsjto provide a relatively shallow refrigerant chamber, said chamber in operating condition being substantially filled with liquidrefrigerant, the inner casing being so formed as to provide a longitudinal freezing chamber for receiving an icy tray, and means for rigidly fastening said casings 'to cach other at a pluralit of points intermediate their-peril'iheries w iereby to prevent defor- 70 mation of the casings under pressures other than atmospheric.

7. Refrigerant liquid storage and evaporating means for lrefrigerating apparatus comprisuwr a formed of? a pair of nested -i-shcet-metal casings spaced apart but having one of said casings joined at its periphery tothe other'of said casiugs to provide a relatively shallow refrigerant chamber, said chamber in operat- 90 ing condition being substantially filled with liquid refrigerant, theinncr casing being so formed as to provide alongitudinal freezing chamber for rcceivingvauice tray, means associated willi the inner casing for supporting said tray, and means for rigidly fastening said casings to cach other at a plurality of oints interna-hate their pcriphcries wherey to prevent deformation of the casings under pressures other than atmospheric, said means comprising a plurality of spaced welded portions.

A heat-absorbing unit for rcfrig 'ating apparatus comprising a horizontally disposed sheet-metal casing so arranged as to form an open ended flcczing compartment for the reception of articles to be frozen, a second sheet-metal casing disposed around the first easing and having a substantial portion of its surface in contact with the first casing but having the remaining portion of its surface spaced therefrom, one of said casings being welded at its periphery to the other of said casings to provideI a closed chamber for containing a substantlal body of liquid refrigerant, and means comprisingr welded portions for uuit-ingthe casings to each other at the points of contact between the first and second casings whereby to pr l vide strength and rigidity against pressures 11n other than atmospheric inside the refrigerant. chamber.

9. A heat-absorbing unit for refrigerating apparatus ucomprising a horizontally disposed slieetnietal casing so arranged astowlls form an open ended freezing compartment for the reception of articles to be frozen, a second sheet-metal casing disposed around the first casing, and having a substantial portion of its surface in contact with the first casing but having the remaining portion of its surface spaced therefrom. one of said casings being welded at its peri )fiery to the other of said casings to prov de a closed chamber for containing a substantial body of liquid refrigerant, means comprising welded portions for uniting thecasinvgs toeachA other atv the points of contact lbetween the" first and second casings 'whereby to providev strength and rigidity against pressiires other "`I3.

fabricated unitary structure 'I5 its surface spaced therefrom, one of said casings being Welded at its periphery to the other of said casings to provide a closed chamber for containing a substantial body of liquid refrigerant, means comprising weld-l ed portions for uniting the casings to each other at the points of contact between the first and second casings whereby to provide strength and rigidity against pressures other than' atmospheric inside the refrigerant chamber, a sheet-metal surge tank or header formed integrally with the outer casing and in open communication with the liquid in the refrigerant chamber, and refrigerantinlet and outlet conduits passing through a Wall of said surge tank.

11. A heat-absorbing unit for refrigerating apparatus comprislng a horizontally disposed sheet-metal casing so arranged as to .form an open ended freezing compartment for the reception of articles to be frozen, a second sheet-metal casing disposed around the first casing, and having a substantial portion of its surface in Contact with the first casing but having the remaining portion of its surface spaced therefrom, one of said casings being welded at its periphery to the other of said casings to provide a closed chamber for containing a substantial body of liquid refrigerant, means comprising Welded portions for uniting the casings `to each other at the points of contact between the first and second casings whereby to provide strength and rigidity against` pressures other than atmospheric inside the refrigerant chamber, and a closure for 'the rear end of the freezing compartment fixedly secured to said casings.

12. A heat-absorbing unit for refrigerating apparatus comprising a horizontally disposed sheet-metal casing so arranged as to from an open ended freezing compartment for the reception of articles to be frozen, a second sheet-metal casing disposed around the first easing, and lia-ving a substantial portion of its surface in contact with the first casing but having the remaining portion of its surface spaced therefrom, one of said casings being welded at its periphery to they other of said easings to provide a closed chamber for containing a substantial body of liquid refrigerant, means comprising welded portions for uniting the casings to each other at the points of contact between the first and second casings whereby to provide strength and rigidity against pressures other than atmospheric inside the refrigerant chamber, said outer casing being provided on its upper surface with an enlarged vintegral portion `forming a'surge tank or header for containing liquid and gaseous refrigerant, said enlarged portion being in open communication with the liquid in the refrigerant chamber.

HERBERT T. HERR. 

